Brazil, China, India and South Africa have urged wealthy nations to hand over $10bn (£6bn) pledged to poor nations in 2010 to fight climate change.
The group - known as Basic - said the money must be available at once "as proof of their commitment" to address the global challenge.
The plea was issued after a meeting of the four nations in Delhi.
The funds were pledged in a non-binding deal agreed at last year's Copenhagen global climate conference.
The deal - the Copenhagen Accord - envisages that $30bn (£18.5bn) of aid will be delivered for developing nations over the next three years.
Basic members were instrumental in fashioning a political accord at the December climate summit.
The next round of negotiations is due to be held in December in Mexico.
After the Delhi talks, environmental ministers from the four nations issued a joint statement calling for rapid distribution of $10bn that industrialised nations promised to the developing world to tackle climate change in 2010.
The first funds should go to the least developed countries, including small island states and African nations, China's top climate negotiator Xi Zhenhua said, the Associated Press reports.
The four nations also broadly endorsed the Copenhagen agreement, the BBC's Sanjoy Majumber in Delhi says.
And they said they would come up with some sort of action-plan on battling global warming, our correspondent adds.
This comes just a week ahead of a deadline for nations signing up to the accord to send figures on how much they will curb emissions.
But amid uncertainty over who is going to sign up, UN climate convention head Yvo de Boer said earlier this week the deadline was "soft".
He said the Copenhagen summit had not delivered the "agreement the world needs" to address climate change.
---- from BBC News